Jarring tool



J. JOHNSON JARRING TOOL- Filed Feb.

June 17, 1941.

5 Sheets-Sheet l June 17, 1941. J JOHNSON 2,245,786

JARRING TOOL Filed Feb. 5, 1940 3 Sheets-Sheet 2 grwm vtom umomm June 17, 1941. J JOHNSON 2245.786

JARRING TOOL Filed Feb. 3, 1940 3 Sheets-Sheet 5 Patented June 17, 194i UNI-TED STATES- PATENT OFFICE Appuefx: 31 542 32511 3 3114 '(c1.255 .27)

14 Claims.

This invention relates to certain new and useful improvements in jarring tools employed in wells and has particular reference to jarring tools useful in connection with drilling tools, production tools and devices, and the like.

The primary object of this invention is to provide a jarring tool operated by hydraulic or pneumatic pressure to actuate the hammer mandrel, thereby creating a jar on the fishing tool.

A further object of this invention is to provide a jarring tool in which the weight and velocity of the hammer mandrel is depended upon to create a jar.

A still further object of the invention is to provide a jarring tool of the above mentioned type having a charge of air or gas above the mandrel piston to equalize the pressure of the hydrostatic column on the outside of the jarring tool and prevent the retarding action of the column on the hammer mandrel.

A still further object of the invention is to provide a jarring tool which is operated automatically without the aid of the drill pipeto effect the jarring motion of the hammermandrel.

Other objects and advantages of the invention will become apparent. during the course of the following description of the accompanying drawings, wherein Figure 1 is a vertical cross-sectional view of the entire jar embodying this invention;

Figure 2 is an enlarged vertical cross-sectional view through the lower end of the jar assembly;

Figure 3 is an enlarged vertical cross-sectional view through the upper portion of the jar illustrating the jar mandrel;

Figure 4 is a vertical cross-sectional view greatly enlarged through the central portion of the Figure 5 is a horizontal cross-sectional, view taken on line 55 of Figure2 looking in the direction of the arrows, illustrating the valves provided in the mandrel piston;

Figure 6 is a horizontal cross-sectional view taken on line i6 of Figure 4, looking in the direction of the arrows showing the lock for maintaining the equalizing valve in an open position after the initial movement of the mandrel;

Figure 7 is a horizontal cross-sectional view taken on line 1-1 of Figure 4, looking in the direction of the arrows, illustrating the arrangement of the ports in the equalizing valve; and

Figure 8 is a horizontal cross-sectional view taken on line 88 of Figure 4, looking in the direction of the arrows illustrating the gripping dog supporting collar; and

pipe section, or the like.

Figure 9 is a fragmentary, longitudinal, sectional view of the upper part of my tool, showing the pneumatic balancing chamber; and Figures 10, 11 and 12 are sectional views.

In the drawings, wherein for the purpose of illustrating the invention and wherein like reference characters will be employed to designate like parts throughout the same, the reference character It will generally be employed to designate a jarring tool, capable of being inserted in a well hole upon a fishing tool for the purpose of jarring a pipe string loose, or attachable to a bit or other tool.

The jarring tool may comprise a lowermost casing section II and an uppermost casing section l2, the former being intemally threaded at each end as at l3 and I4. Secured to the lower end of the casing section II is a closure plug I5,

having the upper end threaded for connection to the threads l3. A chamber I6 is formed in the closure plug I5, and is reduced as at H, forming a guide for a plunger shaft It on the upper end of which is formed a plunger 20, reciprocably mounted in the chamber It. The closure plug is provided with a central bore 2| communicating with the chamber I6, and said chamber is divided in sections threadedly connected as at 22 to allow the removal of the plunger 20 for the purpose of repairs. The plunger shaft I8 is also centrally bored as at 23 terminating at the upper end in a transverse port 24 which communicates with the chamber 16 when the plunger 20 is raised out of engagement with the lower wall 01' the chamber. Diagonal bores 25 are formed in the plunger 20 and have their upper ends terminating in a counter-sunk opening 26 in the top wall of the plunger indirect alinement with the bore 2| of the plug l5.

Screw threads 21 are formed on the lower end of the plunger shaft I8 and are received in a threaded opening formed in the upper end of a pipe section 29, having its lower end threaded as at 30 for connection to a. fishing tool, a bit, a A bore 3| is formed in the pipe section 29 and communicates'with the central bore in the plunger shaft l8.

Intermediate the casing sections I 2 and I3 is a connector section 33, having lateral openings 34 and a central passageway 35, for receivinga slide valve 36, also having lateral openings 3'! adapted to register with the openings when the valve is in its uppermost-position. A spring pressed plunger 38 carried by the upper end of the slide valve is adapted to be received in a locking groove 39 formed in the inner wall of the connector to hold the slide valve in its uppermost position, and with the ports 34, 31 in alinement, after the-initia1 jarring action.

It will be noted that the slide valve is slidably mounted within the connector 33 and the con nector is threaded at each end as at 40 and 4| for receiving the screw threaded ends of the lower and upper casing sections H and I2 respectively.

Screw threads 42 are formed in the upper end of the casing section l2 for receiving the screw threaded reduced end 43 of a drill string connection, or tool joint, 44, centrally bored as at 45, and having its upper end provided with tapered screw threads 46, into which the drill pipe 48' screws. The central bore 45 is reduced at its lowermost end and is provided with internal screw threads for receiving a centrally disposed circulation pipe 41 which extends downwardly through the casing sections H and I2 and terminates a short distance above the closure plug l5. Communicating with the casing section I 2 is a longitudinal passageway 48 controlled by a ball valve 48 mounted in a lateral passageway 50 connecting the upper end of the passage 48, so that air or fluid under pressure may be admitted to the interior of casing section 12 above the connector 88. This chamber A in the casing I 2 may be termed the jarring chamber, and the jarring hammer will move in air or gas and will not be retarded in its movement as though it were moved through a liquid.

Centrally located within the casing sections II and I2 is a mandrel 52 on the upper end of which is fastened or formed a hammer weight 58, and said hammer and mandrel are formed hollow for receiving the vertical wash pipe 41 so that the mandrel and hammer will slide thereon freely. Theupper end of the hammer 58 is provided with a striking face 54 adapted to engage the striking face 55 formed on the drill string connector 44, whereby sudden upward thrusts of the hammer 58 will create a jarring action on the entire jarringtool. The upward movement of the hammer in the chamber A will be unimpeded due to the air or gas occupying the chamber.

A dog engaging face 58 is formed on the enlarged lower end of the mandrel 52, and is formed intermediate cam faces 51, which are adapted to guide the lower end of the mandrel between the ripping dogs, or a grip ring, which will be hereinafter more fully described.

Mounted in the upper end of the enlarged portion of the central bore 2! in screw threads 58 is a. tubular extension 50, having threads ll adapted to enter the threads 58 to rigidly hold the tubular extension in position. The upper end of the tubular extension 80 is provided with inwardly tapering notches 52 for receiving angle brackets 63, which are positioned in diametrically opposed relation and between each adjacent pair of angles, there is bolted a vertically extending gripping dog 84, by means of anchoring bolts 55 having nuts 68 threaded on each end thereof. Formed in the upwardly extending dogs 84 are notches 81 for gripping the lower enlarged and of the mandrel 52 within the notched recess 58 formed therein to hold the mandrel in its lowermost position until forced upwardly by the exertion of pressure passing downwardly through the well string and wash pipe 41. The upper free ends of the gripping dogs 88 taper to allow the spreading action thereof when them-andrel cam faces 51 engage the gripping dogs. Any other suitable means to releasably grip the mandrel 52 may be employed within the scope of my invention.

The lower end of the mandrel is provided with an enlarged bore 10 for receiving a packing 1! held in position by means of a gland nut 12, threaded on the lower end of the bore 10. The packing 1| prevents the escapeof fluid between the mandrel 41 and the wash pipe 52.

Formed integral with the mandrel 52, or flxedly attached thereto, slightly above the lower end thereof, is a piston 14, having packing rings and said piston is capable of reciprocable movement in the lower casing section II, and engages the wall of the section.

Ports 18 extend upwardly through the piston 14 for slidably receiving a valve rod 11, the lower end of which is provided with a valve 18 for closing the port. A coil spring 18 is mounted in an enlarged portion of the bore 15 for normally holding the valve 18 in an open position. The upper end of the valve rod 11 is guided in a guide spider 88 and a nut 8| is threaded on the extreme upper end of the valve rod 11 to prevent the displacement thereof.

Rigidly mounted in the lower casing section II is a collar 82 to the lower end of which is fastened an annulus 88 against which the lower end of'a coil spring 84 abuts, so that the upper end will engage an annulus 85 slidably mounted on guide pins 88 carried by the upper end of the collar 82. The coil spring 84 and annulus 85 are adapted to engage the valves 18 to force the same upon their seats and prevent the escape of fluid under pressure through the piston, when the same is in its lowermost position.v I

A coil spring also surrounds the tubular extension 80 and has its lowermost end engaging the plug pipe section l5, while the upper end engages a washer 8| slidably mounted on the tubular extension 80, so that the washer will exert an upward tension upon the lower, ends 82 of the gripping dogs 84. In this manner, the fl pp g dogs 64 are resiliently urged into engagement with the lower annular recessed end of the mandrel.

It is understood that the drilling fluid flows downwardly in the drill pipe 45'. Above the connection or tool joint 44 and within the drill pipe 45, I provide a tube 88. This tube is fixedly mounted in acollar 84 in the drill string, and is spaced from the wall of the drill pipe, thus providing an air balancing chamber 85. The drilling fluid flowing downwardly in the drill pipe will gradually rise in the jarring tool up to the lower open end of the tube 88. Thus, a quantity of air is trapped above the drilling fluid in the space 85. This trapped air will be compressed and will act as a resilient balancing medium, similar to a surge chamber in a pipe line. This trapped air will tend to create a constant downward pressure of the fluid, which is operating the jarring tool as will be further described. The prime purpose of this air or gas chamber acting upon the actuating fluid is, therefore, to maintain a substantially constant pressure of this actuating fluid within the jarring tool.

For a consideration of the operation of the invention, it will be assumed that the jarring closed, oil is injected'through the opening 50, which is sealed by the ball valve 49 until the level 01' the oil reaches a point slightly above the valve 36. Next, a charge of air or gas would be injected through the valve 50 above the oil to about 1500 pounds, more or less, or an amount suflicient to counteract the hydrostatic pressure of the drilling fluid or mud, at a depth of 3000 i'eet. The jarring tool may be secured to the end of the drill 'pipe string and lowered into the well to the 3000 feet depth, at which operations are to proceed.

Upon insertion of the jarring tool in the well,

' an upward pull is exerted on the drill pipe string to cause the valve plunger to move downwardly in the chamber l5, until the lateral port 24 is closed within the bore l'l'. Fluid under pressure isthen forced by means 01' a pump or the like having its .pressure side connected to the top of the drill pipe string so that the fluid under pressure would pass downwardly through the wash pipes 93 and '41, until it reached a point below the end of the mandrel 52, where a pressure would be exerted upwardly on the piston I4 until the pressure built up was great enough to cause the gripping dogs to release the lower end of the mandrel, whereupon-the mandrel and weight hammer 53 will be forced upwardly, creating a jar when the upper end of the weighted hammer 54 engages the anvil surface 55 in the upper end of the casing section II. Since there is air or gas in the chamber A, the hammer will travel upwardly, in this-air or gasmedium, and will not be restricted as if the hammer were moving in a liquid.

During the initial upward movement of the mandrel, the valve 36 is opened so that the ports 34 and 37 are alined, allowing the pressure in the upper casing section H2, or above the piston 14, to equalize the hydrostatic pressure on the outside of the jarring tool. Also, during the initial movement of the mandrel 52, the valves 18 are opened by the upper ends of the rods contacting the lower portion of the valve 36. After the valve 36 has been moved so that the ports 34 and 31 are .inalinement, the spring pressed plunger 38'will be received in the locking opening 39 to retain the valve in open position.

While the valve 36 is open, a slight rise of pressure in the upper casing section l2, due to an increased displacement in addition to the weight of the hammer 53, will cause the mandrel 52 to drop downwardly, closing the valve 18 and causing the spring gripping dogs 64 to engage and lock the lower end of the mandrel in its original position until the fluid pressure passing downwardly through the wash pipe 41 builds up to again cause the operation of the mandrel with the resultant jarring action being again repeated.

The volume of fluid pumped through the wash pipe 41 must not be great enough to hold the piston 74 in suspension due to friction in the valve ports 76.

After the jarring operation has been completed, a ball 96 is dropped downwardly through the drill pipe string and jarring tool whence it comes to rest upon the floor of the chamber It to hold the plunger 20 in a partially raised position in the chamber l6, so that fluid will not be trapped in the jarring tool and drill pipe string during the removal thereof from the well bore, thereby preventing the pulling of the weight of a column of liquid or mud in addition to the weight of the drill string and jarring tool,

It is to be understood that the form of the invenues herewith shown as deseribed'is to be taken as the preferred embodiment-o1 the same. and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having described my invention, I claim:

1. A jarring tool, including a casing, a man drel reciprocably mounted therein, means to exert pressure against the mandrel to move the.

same upwardly and strike a jarring blow, and means to release the pressure against the man: drel on upward movement or said mandrel, and

an air balanced chamber in. the pressure fluid column whereby the pressure is maintained. substantially constant.

2. A jarring tool, including a casing,- a ma ndrel reciprocably mounted therein, means to exert pressure against the mandrel to move the same upwardly and strike a jarring blow, and. means to release the pressure against the man drel 0n upward movement of saidmandrel, saidv impeded, and an air balanced chamber in .the

above the mandrel, and means for admitting fluid under pressure to the lower side of the mandrel, and latch m'eans engaging the mandrel and releasably restraining said mandrel against upward movement.

4. A jarring tool comprising a casing, a mandrel reciprocably mounted therein, a piston on the mandrel, valve means in the piston for allowing the escape oi fluid under pressure from below the piston to above the piston, and. means for admitting fluid under pressure against the lower side of the mandrel. r

5. A jarring tool comprising a casing, 11- mandrel reciprocably mbunted therein, a piston on the mandrel, valve means in the piston for allowing the escape of fluid 'under'pressure from below the piston to above the piston, and means for admitting fluid under pressure against the lower side of the mandrel, and latch means engaging the mandrel and releasably holding said mandrel against upward jarring movement,

6. A jarring tool, comprising a casing, a fluid pressure pipe extending longitudinally through the casing for admitting fluid under pressure to the lower portion of the casing, a mandrel-reciprocably mounted in the casing, releasable gripping means engaging the mandrel, said fluid pressure pipe conducting the fluid against the underside of the mandrel to urge the mandrel upwardly, whereby a jarring blow is struck, and means to release the fluid under pressure against the mandrel after the mandrel has started its jarring blow.

'7. A jarring tool, comprising a casing, a fluid pressure pipe extending longitudinally through the casing for admitting fluid under pressure to the lower portion of the casing, a mandrel reciprocably mounted in the casing, releasable gripping means engaging the mandrel, said fluid pressure pipe conducting the fluid against the underside of the mandrel to urge the mandrel upwardly, whereby a jarring blow i struck, and

means to release the fluid under pressureagainst the mandrel after the mandrel has started its jarring blow, said casing having a chamber surrounding the upper portion or the mandrel, said chamber being subjected to a gas pressure equalizing the hydrostatic pressure on the outside of the tool.

8. A jarring tool comprising upper and lower casing sections, a fluid pressure pipe extending longitudinally through the casing sections for admitting fluid under pressure to the lower casing section, a mandrel reciprocably mounted on the fluid pressure pipe, a valved piston carried by the mandrel located in the lower casing section, releasable gripping means in the lower casing section engaging the mandrel and said upper casing section being subjected to a pressure equalizing the hydrostatic pressure on the outside of the casing sections.

9. A jarring tool comprising a casing, a fluid pressure pipe extending longitudinally through the casing for admitting fluid under pressure to the lower portion of the casing, a mandrel reciprocably mounted in the casing, releasable ripping means engaging the mandrel, said fluid pressure pipe conducting the fluid against the underside of the mandrel to urge the mandrel upwardly, whereby a jarring blow is struck, and means to release the fluid under pressure against the mandrel after the mandrel has started its jarring blow, said casing having a chamber surrounding the upper portion of the mandrel. said chamber being subjected to a gas pressure equalizing the hydrostatic pressure on the outside 01' the tool, and a balancing chamber in the pressure fluid column whereby a substantially constant pressure is maintained on the jarring tool.

10. A jarring tool comprising a casing, a fluid feed pipe extending longitudinally through the casing for admitting fluid under pressure to the lower part of the casing, a mandrel slidably mounted 'in the casing, releasable gripping SJMEJQB mounted in the casi releasable r ppin meansengaslngthemandrehaplston element onthemandrehsaidfluidunderpremurejan ringagainstthelowersideotthe flstomand fluid release means extending longitudinally thnoughthepistomandmeanstoopensaidfluid release means on upward movement of the mandrel.

12.Ajarringtoolcompriaingaeasing,afluid feed pipe extending longitudinally through the casingior admitting fluidunderprealuretothe lowerpartoi'the casing,amandreislidably mounted in the casing. releasable m8 meansthemandreLaplstonelement onthemandrehsaidfluidunderprmurejarringagainstthelowersideotthepimand fluid release means extending longitudinally throughthepistomandmeanstoopennidflmd releasemeansonupwardtorthemandrel, said casinghaving a gaschambersurrmnding the upper portion oi! the mandrel, said chamber containing gas under a pressure to baianoe thepressureonthemmideotthe tool.

13. A jarring tool comprising upper and lowercasingsectionaaprmmepipeextending longitudinally through the casing sections, a mandrel recipmcably mounted on the pressure pipe,avalvedpiston torthelowerendotthe mandrel adapted to be forced upwardly by fluid pressure admitted through the pressure pipe, releasable grinn dogs tor the lower end of the mandrel and means in the lower portion of the upper casing section for opening the piston valves when the piston reaches the limit or its upward travel.

14. A jarring tool comprising upper and lower casing sections, a longitudinal pressure feed pipe means engaging the mandrel, a piston element on the mandrel, said fluid under pressure jarring against the lowerside of the piston, and fluid feed pipe extending longitudinally through the casing for admitting fluid under pressure to the lower part of the casing, a mandrel slidably extending through the casing sections for feeding fluid under pressure to the lower casing sec tion, a mandrel slidably mounted on the pressure feed pipe, a valved piston reciprocably-mounted in the lower casing section, releasable gripping dogs for the lower end of the mandrel, a weighted hammer formed on the upper end of the mandrel operable inthe upper casing sections, means for admitting fluid under pressure to the upper casing section, and valve means operable by the piston during its initial movement, for allowing the escape of the pressure in the upper casing section to the outside of the jarring tool.

JACK JOHNSON. 

